Refrigerating apparatus



April 13, 1937. J. G. KING 2,076,820

REFRIGERATING APPARATUS Filed Feb. 28, 1955 INVENTOR.

ATTORNEYS Patented Apr. 13, f 1937 REFRIGERATING APPARATUS Jesse G. King, Dayton, Ohio, assignor to General Motors Corporation, Dayton, Ohio, 2. corporation of Delaware Application February 28, 1935, Serial No. 8,611

12 Claims.

This invention relates to refrigerating apparatus and more particularly to an improved control system for domestic electric refrigerators.

Ordinarily domestic electric refrigerators are controlled according to the temperature of the evaporating means. While this provides a fairly satisfactory and simple control, it is often not quickly responsive to the insertion of warm ice trays into the evaporator to immediately start i the freezing thereof. Thus a'certain amount of diately started and in which the system is returned to normal control when the freezing has been accomplished.

Further objects and advantages of the present invention will be apparent from the following description,-reference being had to the accompanying drawing wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 is a fragmentary sectional view of a domestic electric refrigerator and refrigerating system embodying my invention;

, Fig. 2 is a horizontal fragmentary sectional view of a portion of the upper ice tray controlled mechanism, and

Fig. 3 is a fragmentary horizontal sectional view of the lower ice tray and control mechanism. The apparatus disclosed consists essentially of a domestic electric refrigerator having a thermostat switch responsive to evaporator temperature for normally opening and closing the electric circuit of the compressor and means controlled by the complete insertion of the ice tray into the ice tray compartment of the evaporator for providing a shunt across the normal thermostat switch to cause the compressor to operate until another thermostat responsive to the temperature of the ice tray opens the shunt.

Referring to the drawing, there is shown an insulated refrigerator cabinet 20 enclosing a food compartment 22 containing an evaporator 24. Evaporated refrigerant is withdrawn from the evaporator 24 and liquid refrigerant is supmeans 24.

plied to the evaporator 24 by a refrigerant liquefying apparatus including a compressor 26 for compressing the refrigerant and for forwarding the compressed refrigerant to a condenser 28 wherein the compressed refrigerant is liquefied 5 and collected in the receiver 30. From the receiver 30 the liquid refrigerant is forwarded through a supply conduit 32 to a liquid flow control device such as a restrictor 34 which controls the flow of liquid refrigerant to the evaporator 10 24. The evaporator 24 is provided with hollow ice tray shelves 36 and 38 and hollow sheet metal side walls 40 surrounding the ice tray shelves to provide three ice tray compartments.

The liquid refrigerant passing through the flow 15 control device 34 first enters the upper hollow shelf 36 and after passing through the passages within this hollow shelf then flows through the passages in the hollow shelf 38 after which the refrigerant flows through the passages in the 20 side Wall 40. The refrigerant evaporates in the course of its passage through the hollow shelves and the hollow side walls and this evaporated refrigerant is returned to the compressor through the return conduit 42. 25

The compressor 26 is driven by an electric motor 44 which is supplied with electric energy through an electric circuit 46. Connectedinto the electric circuit in series with the electric motor 44 are a plurality of switches all of which 30 are connected in parallel to each other, One of these switches 48 is a snap acting switch controlled by a thermostat bulb 50 in heat exchange relation with a side wall of the evaporating This switch normally controls the 35 operation of the compressor according to the temperature of the evaporator. However, when warm ice trays are placed upon the ice tray shelves of the evaporator it takes a considerable length of time before the entire evaporator be- 40 comes warm enough to cause the switch 48 to be closed. This delays the freezing of ice and therefore increases the complete ice freezing time. In order to overcome this objection I have provided upon the ice tray 52 which rests upon 45 the hollow shelf 36 a control means generally designated by the reference character 54 which is connected in parallel with the normal control switch 48 so that it may independently close the electric circuit 46 of the compressor motor 44. 5

Referring more particularly to Fig. 2 for a disclosure of this control means 54, I have provided an insulated member which is riveted to the rear wall of the ice tray and which has the plug type of connectors 62 which project into a socket 64 riveted to the rear wall 66 of the evaporator. The insulated member 60 has a cavity 88 therein directly adjacent the rear wall of the ice tray 52. Within this cavity supported at its center point by a pin I8 is a bimetal snap disc 80 which is provided with contacts 82 and 84 adapted to engage, when the temperature is above freezing, the cooperating contacts 86 and 88 which are connected to the plug connectors 62.

10 Thus when the ice tray is filled with water and placed upon its ice tray shelf and moved rearwardly so that the connectors engage their socket, an electric circuit which is in parallel with the shunt circuit is closed to close the compressor motor circuit to immediately start the compressor. When the water in the ice tray has frozen and the temperature goes below freezing a predetermined amount, the bimetal snap disc 80 is cooled below freezing, causing it to snap away from the stationary contacts 86 and 88 to break the electrical connection across the plug connec tors to open the shunt. In this way freezing is started immediately by this abnormal control which control is disconnected when freezing is completed.

The ice tray I02 upon the shelf 38 is likewise provided with a control means I04 which is in parallel electric circuit relation with the control means 54 of the ice tray 52 as well as being in parallel electric circuit relation with the normal snap acting control switch 48. This control means, however, employs a slightly different scheme of operation. In this form an insulating housing member I06 is riveted to the rear wall of the ice tray I02 and provided with a cavity I08 which communicates directly with the rear wall of the ice tray. This cavity is provided with an annular flange IIO which receives the outer edge of a bimetal snap disc II2 which outer edge is held in place by a metal ring I I4. Connected to the center portion of the snap disc is a pin IIG which extends through an aperture in the wall of the housing member I06.- Upon the rear face of the housing member is fastened a metal member 46 H8 which has two projecting portions for engaging and bridging the contacts I20 and I22 provided upon a floating contact member I24 of in-' sulating material which is normally spring pressed by the coil springs I28 against the flange of the 50 metal housing member I30 which is fastened to the rear wall of the evaporator 24. I

When the ice tray is inserted in place on its ice tray shelf 38 the projecting portions of the connecting metal member I I8 on the rear face of the housing I 08 engages the contacts I20 ,and I22 to close the circuit of the electric motor 44 to start the operation of the compressor. When the water within the ice tray is frozen the bimetal snap disc H2 is cooled, thus causing its center portion to move away from the rear wall of the ice tray and to move the pin I I6 also away from the rear wall of the ice tray to push the floating contact member I24 away from the ice tray to separate the contact members I20 and I22 from the metal bridging member I I8 to again open the electric motor circuit. Thus with this scheme the circuit is closed when the warm ice tray containing the water to be frozen is inserted and the circuit is opened when freezing is completed. Nor-'- mally the ice tray will remain in a fixed position upon the shelf and the providing of the floating contact member I24 will permit the opening of the electric circuit by the snap disc. Thus I have provided an improved refrigerating system which is responsive to the insertion of warm ce trays into the refrigerator which also properly takes care of the refrigeration when no ice freezing is required.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. Refrigerating apparatus including a liquefying means and an evaporating means, an ice tray in heat exchange relation with the evaporating means, an electric circuit for controlling the operation of the liquefying means, said ice tray having electric contact means adapted to engage a portion of said circuit for closing the electric circuit and means responsive to the temperature of the ice tray for opening the electric circuit, and a second temperature responsive means independent of said first mentioned temperature responsive means for opening the electric circuit.

2. Refrigerating apparatus including a liquefying means and an evaporating means, an ice tray in heat exchange relation with the evaporating means, an electric circuit for controlling the operation of the liquefying means, said ice tray having electric contact means adapted to engage a portion of said circuit for closing the electric circuit and temperature responsive means for opening the electric circuit.

3. Refrigerating apparatus including a liquefying means and an evaporating means, an ice tray in heat exchange relation with the evaporating means, an electric circuit for controlling the operation of the liquefying means, said ice tray having electric contact means adapted to engage a portion of said circuit for closing the electric circuit.

4. Refrigerating apparatus including a cooling element and means for circulating a refrigerant medium through said element, means for controlling the operation of said circulating means, a receptacle adapted to contain a substance to be congealed or frozen, 9, second means for controlling the operation of said circulating means,

the two said controlling means being separate from and operable independently of one another, and one of said controlling means being rendered eilective automatically by the placing of the receptacle into heat exchange relation with said cooling element.

5. Refrigerating apparatus including a. cooling element and means for circulating a refrigerant medium through said element, means for controlling the operation of said circulating means to normally maintain said cooling element between predetermined temperature limits, a receptacle adapted to contain a substance to be congealed or frozen, a second means for controlling the operation of said circulating means, said second named controlling means being separate from and operable independently of said first named controlling means, and said second named controlling means being rendered 'efiective automatically by the placing of the receptacle into heat exchange relation with said cooling element.

6. Refrigerating apparatus including a cooling element and means for circulating a refrigerant medium through said element, means for controlling the operation of said circulating means to normally maintain said cooling element between predetermined temperature limits, a receptacle adapted to contain a substance to controlling means.

be congealed or frozen, a second means for controlling the operation of said circulating means, said second named controlling means being separate from and operable independently of said first named controlling means, said second named controlling means being rendered effective automatically by the placing of the receptacle into heat exchange relation with said cooling element, and means for rendering said second named controlling means ineffective to place the circulating means under the control of said first named 7. Refrigerating apparatus including a cooling element and means for circulating a refrigerant medium through said element, means for controlling the operation of said circulating means to normally maintain said cooling element between predetermined temperature limits, a receptacle adapted to contain a substance to be congealed or frozen, a second means for controlling the operation of said circulating means,

said second named controlling means being separate from and operable independently of said first named controlling means, said second named controlling means being rendered effective automatically by the placing of the receptacle into heat exchange relation with said cooling element, and temperature responsive means for rendering said second named controlling means ineifective to place the circulating means under the control of said first named controlling means. I

8. Refrigerating apparatus including a cooling element and means for circulating a refrigerant medium through said element, means for controlling the operation of said circulating means to normally maintain said cooling element between predetermined temperature limits, a receptacle adapted to contain a substance to be congealed or frozen, a second means for con trolling the operation of said circulating means, said second named controlling means being separate from and operable independently of said first named controlling means, said second named controlling means being rendered effective automatically by the placing of the receptacle into heat exchange relation with said cooling element to render said first named controlling means ineffective for controlling said circulating means, and temperature responsive means for rendering said second named controlling means ineffective and said first named controlling means eifective erable independently of said first named controlling means, and'said second named controlling means being rendered effective automatically by the placing of the receptacle into heat exchange relation with said cooling element to render said first named controlling means ineifective for controlling said circulating means.

10. Refrigerating apparatus including a cooling element and means for circulating a refrigerant medium through said element, electrically operated means for driving said circulating means, an electric circuit connecting said electrically operated means to a source of supply, means interposed'in said electric circuit for controlling the operation of said circulating means, a receptacle adapted to contain a substance to be congealed or frozen, a second means interposed in said electric circuit for controlling the operation of said circulating means, said second named controlling means being separate from and operable independently of said first named controlling means, said second named controlling means being rendered effective automatically by the placing of the receptacle into heat exchange relation with said cooling element to render said first named controlling means ineffective for controlling said circulating means, and temperature responsive means for rendering said second named controlling means ineffective and said first named controlling means effective to control said circulating means.

11. A refrigerating apparatus including a cooling element, means for'circulating a refrigerant medium through said cooling element, a control for normally controlling the operation of said circulating means to maintain said cooling element at a substantially uniform temperature, a receptacle for containing a substance to be congealed or frozen and adapted to be placed in intimate heat exchange relation with said cooling element, means for rendering said normal consaid last named means being adapted to control the operation of said circulating means independently of said normal control, and said last named means being rendered effective by the act of placing the receptacle in heat exchange relation with said cooling element.

12. A refrigerating apparatus including a cooling element, means for circulating a refrigerant medium through said cooling element, a control for normally controlling the operation of said circulating means to maintain said cooling element at a substantially uniform temperature, a receptacle for containing a substance to be congealed or frozen and adapted to be placed in intimate heat exchange relation with said cooling element, means for rendering said normal control ineifective to control said circulating means, said last named means being adapted to control the operation of said circulating means independently of said normal control, said last named means being rendered effective by the act of placing the receptacle in heat exchange relation with said cooling element, and means for rendering said receptacle ineffective to render said normal control ineffective to thereby return said circulating means to the control of said normal control.

I JESSE G. KING. 

